Presently, the delivery options available to insulin dependent diabetics for insulin delivery include direct injections with a syringe, continuous-delivery with an insulin pump and injections with a jet-spray. Each one of these insulin delivery options has advantages, disadvantages and limitations with respect to factors such as convenience, cost, effort, safety, reliability and pain. Accordingly, selection of an acceptable delivery option by a diabetic will depend on the advantages of a selected insulin delivery option as well as the diabetic's ability and willingness to tolerate the limitations and disadvantages of the selected insulin delivery option.
One of the most reliable methods of insulin delivery that a diabetic can choose is direct injection with a syringe (i.e., an injection needle pierces the skin). Direct injection with a syringe offers precise measurement of insulin and the security of manual delivery. However, direct injection with a syringe sometimes necessitates multiple injections during the course of a day. For example, a Type-1 diabetic generally needs a dosage of insulin either immediately before or after a meal.
For many diabetics, their aversion to needles precludes them from ever being able to bring themselves to direct injection with a syringe. For other diabetics, multiple direct injections per day and bruises at the injection site become too much to tolerate. Regardless of the particular reason or reasons, there are a large number of diabetics who cannot bring themselves to inject their insulin directly with a needle or who lose their ability to tolerate direct injections with a syringe. These diabetics often under-medicate themselves, endangering their physical health and mental well being.
Many diabetics who choose not to subject themselves to multiple direct injections with a syringe, because they have a fear of needles and/or because they bruise easily, look to other options besides direct injections with a syringe. For those who simply have a fear of needles, but are able to tolerate the pain and bruises associated with injection needles, jet spray injection is an option. Jet spray injection delivers a fine stream of insulin through the skin under extreme high pressure. Although a needle is not used, jet spray injection exhibits a similar level of pain and bruising associated with its use as do direct injections with a syringe.
The insulin pump has become the most popular option for diabetics who cannot face multiple daily direct injections with a syringe. With the insulin pump, a diabetic receives a continuous dosage of insulin from a pump apparatus via an infusion device mounted on their body. Insulin is supplied (e.g., pumped) from the insulin pump through a tube to the infusion device. Infusion devices generally include a cannula mounting in a subcutaneous manner within the flesh of the diabetic. The infusion device includes a channel that transmits insulin from an inlet port to the cannula for being delivered to the subcutaneous tissue layer of the diabetic.
Mounting of the infusion device generally involves the use of an insertion needle. Most conventional infusion devices have an insertion needle that extends through a body of the device and through the cannula. During mounting of such a conventional infusion device, the insertion needle serves to pierce the skin and to support the cannula, as most cannulas are made from a soft and/or flexible material. Accordingly, the diabetic still must deal with a needle piecing their skin. However, because the infusion device may remain in place for an extended period of time (e.g., typically up to 3 days or more), the diabetic need only deal with one injection type needle over 3 or more days, rather than multiple times per day. This extended period of time between needle insertions is what makes the pump tolerable for many diabetics who have an aversion to being pierced with injection needles.
The advantages of the insulin pump do not come without a number of significant disadvantages. One disadvantage is that the precise measurement of insulin and the security of manual delivery associated with direct injections with a syringe are largely turned over to the insulin pump. Situations such as the pump malfunctioning, degradation of the insulin within the pump reservoir (e.g., due to heat), bubbles in the reservoir/supply tube of the pump (e.g., due to agitation) and inherent limitations of an electromechanical device often result in the pump delivering an incorrect dosage of insulin. As the pump is a continuous delivery device, the diabetic may not know that they are receiving an incorrect dosage of insulin until a lengthy period of time has passed, resulting in dangerous blood-sugar levels. Another disadvantage is that the insulin pump, which is about the size of a typical pager, must be worn essentially 24 hours per day. Finding an inconspicuous yet convenient place to wear the pump can be difficult. Still another disadvantage is the cost of the insulin pump—about $8000 for the pump, plus disposable supplies. Though insurance plans generally cover insulin pumps, the considerable price of the pump adversely affects insurance premiums. Furthermore, under certain insurance policies, the insured party may still have the responsibility of paying for at least a portion of the pump.
Therefore, a device and method for enabling a frequently administered medication to be injected with a syringe in a manner that overcomes limitations associated with conventional medication delivery devices and methods.